Daniel w



(No Model.)

D. W. KETGHAM.

AUTOMATIC GUT-OFF FOB. GAS BURNERS. I No. 586.499. v Patented July 13, 1897.

Mummml l H winumuazaazav E rimnoams mans cc mom-H \usummu, nit:

UNITED STATES PATENT OFFICE.

DANIEL W. KETCHAM, OF THE UNITED STATES ARMY.

AUTOMATIC CUT-O'FF FOR GAS-BURNERS.

SPECIFICATION formi'n g part of Letters Patent N 0. 586,499, dated July 13, 1897.

Application filed February 12, 1897. Serial No. 623,157. (No model.)

To all whmn it-may concern:

Be it known that I, DANIEL W. KETCHAM, second lieutenant, Second Artillery, United States Army, a citizen of the United States, stationed at Fort XVarren, State of Massachusetts, have invented certain new and useful Improvements in Automatic Out-Ofis for Gas- Burners; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to improvements in automatic cut-offs for gas-burners, and more particularly to a device for preventing the escape of illuminatingas when the gas is not lighted.

The object of my invention is to prevent accidental asphyxiation, so often caused by the gas being put out by accident or otherwise while it is still turned on and allowing it to escape in the room, by a device which is both certain in its action and simple in its construction.

In order to fully describe my invention, reference is had to the accompanying drawings, in which similar letters refer to similar parts throughout the several views.

Figure 1 represents my improved device in side elevation, showing the same applied to a gas-burner when the gas is lighted. Fig. 2 represents a plan view of the weight-arm and electromagnets with portions of the gas-pipe broken away. Fig. 3 represents my improved device in side elevation, showing the position of the weight-arm when the gas is not lighted. Fig. 4 represents a central longitudinal sec-, tional View of the weight-arm; and Fig. 5 represents an enlarged detail View in section of the lug of the weight-arm which engages the valve, showing the manner in which the same is attached to the valve.

A represents an ordinary gas-burner, to which I attach a small receptacle B, of glass or other substance or substances being nonconductors of electricity, having the enlarged bottom I) and narrow neck 19. The said receptacle is provided with the terminals 5 and 12 preferably of platinum wire, which pass into the receptacle through the bottom and neck, respectively. This receptacle B is fitted to a point near the bottom of the terminal b with mercury and is mounted on the burner A sufficiently near the flame of the gas to render the mercury sensible to the heat of the flame. The terminal 19 passing through the neck of the receptacle B, is connected by means of a conductor with the magnetizingcoils c of an electromagnet O, mounted upon the gas-,piperD, and the other terminal of the said magnetizing-coil is connected to one of the polesjof a battery E, the other pole ofthe said battery beingoconnected with the terminal b? at the bottom of thereceptacle B.

H represents a metallic weight-arm mounted, as shown, on the valve F of the gas-pipe. This arm H is so mounted on the valve F that when the arm is in the horizontal position the gas will flow through the pipe to the burner, and when the arm occupies the vertical position, as shown in Fig. 3, the gas will be cut off from the burner, all of which will be more fully described hereinafter. The arm H is made hollow, as shown in Fig. 4, and divided into three chambers K, L, and M. The chambers K and L communicate with each other through the small orifices h and h, the former being provided with the regulating-screw k by which the size of the said orifice it may be varied.

Enough liquid, as water, oil, mercury, or other suitable liquid,is placed in the weightarm H as to almost fill the chamber L, and when the arm is in the vertical position the liquid will flow from L through h into is and remain in that chamber. Now the weight of the arm H is so distributed relative to its pivotal point of support that the arm will remain balanced in the horizontal position-as long as it contains no liquid.

When the arm H containing liquid is raised from the vertical to the horizontal position, the liquidin the chamberK will obviously flow from the end it of that chamber toward the end 10 of the same and then through the orifice hinto the chamber L, the rapidity to the right of the point of support of the arm the said arm will fall to the vertical position, as shown in Fig. 3, and then the liquid in chamber L will fiow through orifice h into chamber K. On the inner face of the arm H and near one end is fixed an iron plate or armature P, the function of which is to be attracted by the electromagnet.

In order that the gas may be turned low while the arm is still in the horizontal position, the arrangement as shown in Fig. 5 is provided. This consists of forming on the bearing-surface of the lug N a small lug n, which is adapted to work in the slot f of the valve F. hen the arm is raised to the horizontal position, the lug will engage the shoulder f and the gas will be turned on to its fullest extent, but by turning the valve backthat is, by making the shoulder f recede from the lug n-the flow of the gas may be varied within any limits dependent upon the length of the slot f.

The operation of the device is as follows: hen the gas is not lighted, the apparatus is in the position as shown in Fig. 3, but when it is desired to light the gas the arm H is raised to the position as shown in Fig. 1,

4 which allows the gas to flow to the burner when it is lighted. The gas is turned on and off, as in ordinary burners, the valve being provided with the head F for this purpose. Vhen the gas is lighted, the heat from the flame causes the mercury in the receptacle B to expand, and when it does so sufficiently to rise in the neck of the receptacle and come in contact with the terminal 11 the electrical circuit is completed through the battery and magnets, and hence the magnets becoming energized attract the armature P of the arm H and hold the said arm in a horizontal position as long as the circuit is complete. Before the circuit is complete the arm is held in the horizontal position by the liquid which has flowed to K but if the gas is blown out or put out in any other way, by accident or otherwise, the mercury will, owing to the absence of the heat, contract, leaving the terminal b and thus breaking the electrical circuit. lVhen the circuit is broken, the magnets become no longer energized, and the arm 11 accordingly drops to the position as shown in Fig. 3, which shuts off the gas. If the arm H is raised and the mercury fails to expand, the arm will fall and out off the gas as soon as the liquid flows from the chamber K to L, which will not be long enough for enough gas to have escaped to do any damage. If the gas is blown out, it will escape only until the mercury contracts, when the weight will fall, owing to the preponderance of weight due to the liquid in the chamber L.

Should the circuit at any time get out of order, the gas may be turned on and 01f and used as in ordinary burners, first closing the passage h by the screw 7L2.

It is obvious that my invention is capable of many modifications as-regards the shape and disposition of the different parts, and the method of mounting the arm H on the ordinary valve F. For example, the method shown in Fig. at may be dispensed with and the lug not allowed the play as shown in that structure, and indeed there are many other modifications which may be made without departing from the spirit of my invention; and, again, the shape and method of attaching the receptacle B is obviously capable of many modifications,as it may be placed either above or below the flame, or inside of the burner,

and indeed in many other positions than that shown.

What I claim, and desire to secure by Letters Patent of the United States, is

1. In a safety device for gas-burners, the combination with an arm attached to the valve of the gas-pipe and having interior chambers adapted to be partially filled with a liquid, of an electromagnet adapted, when excited, to attract said arm; a source of electricity connected to said magnet for exciting the same, and means for completing the electric circuit through said magnet-coils at such times as the gas is lighted substantially as described.

2. In a safety device for gas-burners, the combination with an arm secured to the valve of the gas-pipe, and having interior chambers adapted to be partially filled with a liquid, so that the liquid will create a preponderance of weight on either one side or the other of the point of support of the said arm, of an electromagnet adapted, when excited, to attract the said arm; a source of electricity connected to the coils of said magnet; a receptacle partially filled with mercury and mounted near the tip of the gas-burner; an electric conductor passing through the upper portion of said receptacle and not in contact with said mercury when the gas is normally turned off, and a conductor passing through the lower portion of said receptacle and extending into said mercury, one of the said conductors being connected to the source of electricity and the other to the coils of the said magnet substantially as described.

3. In a safety device for gas-burners, the combination with an arm secured to the valve of the gas-pipe, and havinginterior chambers adapted to be partially filled with a liquid, the chambers so arranged and the liquid so controlled as to cause the liquid to create a preponderance of weight on one side of the point of support holding the arm in the horizontal position before the electric circuit is completed, and to transfer this preponderance to the other side of the point of support, after the circuit is completed, in causing the said arm to fall after the circuit is broken; of an electromagnet adapted, when excited, to attract the said arm; a source of electricity connected to the coils of said magnet; a receptacle partially filled with mercury and mounted near the tip of the gas-burner; an trioity and the other to the coils of the said electric conductor passing through the upper magnet, substantially as described. [0 portion of said receptacle and not in contact I In testimony whereof I affix my signature with said mercury when the gas is normally in presence of two Witnesses.

5 turned oif, and a conductor passing through DANIEL W. KETCHAM.

the lower portion of said receptacle and eX- "Witnesses: tendinginto said mercury, one of the said oon- E. T. O. RICHMOND,

ductors being connected to the source of elec- SEBREE SMITH. 

